export function randString(length: number) {
    const strValue = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ';
    const strLength = strValue.length;
    if (length <= 0) {
        return '';
    }
    let result = '';
    for (let i = 0; i < length; i++) {
        const index = Math.floor(Math.random() * strLength);
        result = result + strValue.charAt(index);
    }
    return result;
}